Short Answer 
Kinetic energy, calculated using the formula K = 0.5 * m * v¬≤, quantifies an object’s energy in motion. In a specific example, the initial kinetic energy at 4.5 m/s was 1215 J and final kinetic energy at 3.5 m/s was 725 J, resulting in a kinetic energy loss of 480 J.
Step 1: Understanding Kinetic Energy
The concept of kinetic energy is essential in physics, as it quantifies the energy of an object in motion. The formula for calculating kinetic energy is represented as:
- K = 0.5 * m * v²
Where K is kinetic energy, m is mass, and v is the velocity of the object.
Step 2: Calculating Initial and Final Kinetic Energy
To determine the amount of energy lost during an event, we need to calculate both the initial and final kinetic energy using the given parameters. For our example:
- Initial Kinetic Energy (v = 4.5 m/s): K = 0.5 * 120 * (4.5)² = 1215 J
- Final Kinetic Energy (v = 3.5 m/s): K = 0.5 * 120 * (3.5)² = 725 J
Step 3: Determining Kinetic Energy Lost
Once we have both kinetic energy values, we can find the energy lost during the process by subtracting the final kinetic energy from the initial kinetic energy:
- Energy Lost (KL) = Initial Kinetic Energy – Final Kinetic Energy
- KL = 1215 J – 725 J = 480 J
This results in a kinetic energy loss of 480 J.